[TYPO3-english] mm_forum install: configuration module stuck

[jaco graaff]

I was able to configure mm_forum through the static field in

Template > Home(root) > Info/Modify > Main TypoScript Template > constants
as described in
http://typo3.org/documentation/document-library/extension-manuals/mm_forum/1.8.2/view/1/5/


but now I also want to do:
http://typo3.org/documentation/document-library/extension-manuals/mm_forum/1.8.2/view/1/6/

my mm_forum module is still stuck as seen in the previously attached image - 
clicking the dropdown or the save button does not help

I can do 3 things:

1. Try and clean up database, temp files, etc...

2. Uninstall and re-install mm_forum

3. Do all config through typoscript - but then I will never have the nice 
workflow features of the mm_forum module